When your giving anal and the receiving participator shits onto the penis of the giver who then proceeds to piss out shitty piss into the receivers mouth.

Giver- Yeah that feels so goooood
Receiver- It feels, TO good!
*Receiver excretes from anus*
Receiver- Oh no I'm so sorry!
Giver- Its no problem, I'm used to it. Why dont you suck all the shit off?, we can do a good ol' fuck-shit-piss!
Receiver- Sounds like a plan!